/*
 * Copyright (C) 2009 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.afd.ozblip.photo;

import android.app.ProgressDialog;
import android.content.ContentResolver;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Rect;
import android.net.Uri;
import android.os.Handler;
import android.os.ParcelFileDescriptor;

import java.io.Closeable;
import java.io.FileDescriptor;
import java.io.IOException;

/**
 * Collection of utility functions used in this package.
 */
public final class Util {
    /*
     * Compute the sample size as a function of minSideLength and
     * maxNumOfPixels. minSideLength is used to specify that minimal width or
     * height of a bitmap. maxNumOfPixels is used to specify the maximal size in
     * pixels that is tolerable in terms of memory usage. The function returns a
     * sample size based on the constraints. Both size and minSideLength can be
     * passed in as IImage.UNCONSTRAINED, which indicates no care of the
     * corresponding constraint. The functions prefers returning a sample size
     * that generates a smaller bitmap, unless minSideLength =
     * IImage.UNCONSTRAINED. Also, the function rounds up the sample size to a
     * power of 2 or multiple of 8 because BitmapFactory only honors sample size
     * this way. For example, BitmapFactory downsamples an image by 2 even
     * though the request is 3. So we round up the sample size to avoid OOM.
     */
    public static int computeSampleSize(BitmapFactory.Options options,
            int minSideLength, int maxNumOfPixels) {
        int initialSize = computeInitialSampleSize(options, minSideLength,
                maxNumOfPixels);

        int roundedSize;
        if (initialSize <= 8) {
            roundedSize = 1;
            while (roundedSize < initialSize) {
                roundedSize <<= 1;
            }
        } else {
            roundedSize = (initialSize + 7) / 8 * 8;
        }

        return roundedSize;
    }

    private static int computeInitialSampleSize(BitmapFactory.Options options,
            int minSideLength, int maxNumOfPixels) {
        double w = options.outWidth;
        double h = options.outHeight;

        int lowerBound = (maxNumOfPixels == IImage.UNCONSTRAINED) ? 1
                : (int) Math.ceil(Math.sqrt(w * h / maxNumOfPixels));
        int upperBound = (minSideLength == IImage.UNCONSTRAINED) ? 128
                : (int) Math.min(Math.floor(w / minSideLength),
                        Math.floor(h / minSideLength));

        if (upperBound < lowerBound) {
            // return the larger one when there is no overlapping zone.
            return lowerBound;
        }

        if ((maxNumOfPixels == IImage.UNCONSTRAINED)
                && (minSideLength == IImage.UNCONSTRAINED)) {
            return 1;
        } else if (minSideLength == IImage.UNCONSTRAINED) {
            return lowerBound;
        } else {
            return upperBound;
        }
    }

    // Whether we should recycle the input (unless the output is the input).
    public static final boolean RECYCLE_INPUT = true;

    // public static final boolean NO_RECYCLE_INPUT = false;

    public static Bitmap transform(Matrix scaler, Bitmap source,
            int targetWidth, int targetHeight, boolean scaleUp, boolean recycle) {
        int deltaX = source.getWidth() - targetWidth;
        int deltaY = source.getHeight() - targetHeight;
        if (!scaleUp && (deltaX < 0 || deltaY < 0)) {
            /*
             * In this case the bitmap is smaller, at least in one dimension,
             * than the target. Transform it by placing as much of the image as
             * possible into the target and leaving the top/bottom or left/right
             * (or both) black.
             */
            Bitmap b2 = Bitmap.createBitmap(targetWidth, targetHeight,
                    Bitmap.Config.ARGB_8888);
            Canvas c = new Canvas(b2);

            int deltaXHalf = Math.max(0, deltaX / 2);
            int deltaYHalf = Math.max(0, deltaY / 2);
            Rect src = new Rect(deltaXHalf, deltaYHalf, deltaXHalf
                    + Math.min(targetWidth, source.getWidth()), deltaYHalf
                    + Math.min(targetHeight, source.getHeight()));
            int dstX = (targetWidth - src.width()) / 2;
            int dstY = (targetHeight - src.height()) / 2;
            Rect dst = new Rect(dstX, dstY, targetWidth - dstX, targetHeight
                    - dstY);
            c.drawBitmap(source, src, dst, null);
            if (recycle) {
                source.recycle();
            }
            return b2;
        }
        float bitmapWidthF = source.getWidth();
        float bitmapHeightF = source.getHeight();

        float bitmapAspect = bitmapWidthF / bitmapHeightF;
        float viewAspect = (float) targetWidth / targetHeight;

        if (bitmapAspect > viewAspect) {
            float scale = targetHeight / bitmapHeightF;
            if (scale < .9F || scale > 1F) {
                scaler.setScale(scale, scale);
            } else {
                scaler = null;
            }
        } else {
            float scale = targetWidth / bitmapWidthF;
            if (scale < .9F || scale > 1F) {
                scaler.setScale(scale, scale);
            } else {
                scaler = null;
            }
        }

        Bitmap b1;
        if (scaler != null) {
            // this is used for minithumb and crop, so we want to filter here.
            b1 = Bitmap.createBitmap(source, 0, 0, source.getWidth(),
                    source.getHeight(), scaler, true);
        } else {
            b1 = source;
        }

        if (recycle && b1 != source) {
            source.recycle();
        }

        int dx1 = Math.max(0, b1.getWidth() - targetWidth);
        int dy1 = Math.max(0, b1.getHeight() - targetHeight);

        Bitmap b2 = Bitmap.createBitmap(b1, dx1 / 2, dy1 / 2, targetWidth,
                targetHeight);

        if (b2 != b1) {
            if (recycle || b1 != source) {
                b1.recycle();
            }
        }

        return b2;
    }

    public static void closeSilently(Closeable c) {
        if (c == null)
            return;
        try {
            c.close();
        } catch (Throwable t) {
            // do nothing
        }
    }

    public static void closeSilently(ParcelFileDescriptor c) {
        if (c == null)
            return;
        try {
            c.close();
        } catch (Throwable t) {
            // do nothing
        }
    }

    public static Bitmap makeBitmap(int minSideLength, int maxNumOfPixels,
            ParcelFileDescriptor pfd, boolean useNative) {
        BitmapFactory.Options options = null;
        if (useNative) {
            options = createNativeAllocOptions();
        }
        return makeBitmap(minSideLength, maxNumOfPixels, null, null, pfd,
                options);
    }

    public static Bitmap makeBitmap(int minSideLength, int maxNumOfPixels,
            Uri uri, ContentResolver cr, ParcelFileDescriptor pfd,
            BitmapFactory.Options options) {
        try {
            if (pfd == null)
                pfd = makeInputStream(uri, cr);
            if (pfd == null)
                return null;
            if (options == null)
                options = new BitmapFactory.Options();

            FileDescriptor fd = pfd.getFileDescriptor();
            options.inJustDecodeBounds = true;
            BitmapManager.instance().decodeFileDescriptor(fd, options);
            if (options.mCancel || options.outWidth == -1
                    || options.outHeight == -1) {
                return null;
            }
            options.inSampleSize = computeSampleSize(options, minSideLength,
                    maxNumOfPixels);
            options.inJustDecodeBounds = false;

            options.inDither = false;
            options.inPreferredConfig = Bitmap.Config.ARGB_8888;
            return BitmapManager.instance().decodeFileDescriptor(fd, options);
        } catch (OutOfMemoryError ex) {
            // Log.e(TAG, "Got oom exception ", ex);
            return null;
        } finally {
            closeSilently(pfd);
        }
    }

    private static ParcelFileDescriptor makeInputStream(Uri uri,
            ContentResolver cr) {
        try {
            return cr.openFileDescriptor(uri, "r");
        } catch (IOException ex) {
            return null;
        }
    }

    // Returns Options that set the puregeable flag for Bitmap decode.
    public static BitmapFactory.Options createNativeAllocOptions() {
        return new BitmapFactory.Options();
    }

    private static final class BackgroundJob extends
            MonitoredActivity.LifeCycleAdapter implements Runnable {

        private final MonitoredActivity mActivity;
        private final ProgressDialog mDialog;
        private final Runnable mJob;
        private final Handler mHandler;
        private final Runnable mCleanupRunner = new Runnable() {
            public void run() {
                mActivity.removeLifeCycleListener(BackgroundJob.this);
                if (mDialog.getWindow() != null)
                    mDialog.dismiss();
            }
        };

        public BackgroundJob(MonitoredActivity activity, Runnable job,
                ProgressDialog dialog, Handler handler) {
            mActivity = activity;
            mDialog = dialog;
            mJob = job;
            mActivity.addLifeCycleListener(this);
            mHandler = handler;
        }

        public void run() {
            try {
                mJob.run();
            } finally {
                mHandler.post(mCleanupRunner);
            }
        }

        @Override
        public void onActivityDestroyed(MonitoredActivity activity) {
            // We get here only when the onDestroyed being called before
            // the mCleanupRunner. So, run it now and remove it from the queue
            mCleanupRunner.run();
            mHandler.removeCallbacks(mCleanupRunner);
        }

        @Override
        public void onActivityStopped(MonitoredActivity activity) {
            mDialog.hide();
        }

        @Override
        public void onActivityStarted(MonitoredActivity activity) {
            mDialog.show();
        }
    }

    public static void startBackgroundJob(MonitoredActivity activity,
            String title, String message, Runnable job, Handler handler) {
        // Make the progress dialog uncancelable, so that we can gurantee
        // the thread will be done before the activity getting destroyed.
        ProgressDialog dialog = ProgressDialog.show(activity, title, message,
                true, false);
        new Thread(new BackgroundJob(activity, job, dialog, handler)).start();
    }

    // private static final String TAG = "Util";
    // public static final int DIRECTION_LEFT = 0;
    // public static final int DIRECTION_RIGHT = 1;
    // public static final int DIRECTION_UP = 2;
    // public static final int DIRECTION_DOWN = 3;
    //
    // private static OnClickListener sNullOnClickListener;
    //
    // // private Util() {
    // // }
    //
    // // Rotates the bitmap by the specified degree.
    // // If a new bitmap is created, the original bitmap is recycled.
    // public static Bitmap rotate(Bitmap b, int degrees) {
    // if (degrees != 0 && b != null) {
    // Matrix m = new Matrix();
    // m.setRotate(degrees, (float) b.getWidth() / 2,
    // (float) b.getHeight() / 2);
    // try {
    // Bitmap b2 = Bitmap.createBitmap(b, 0, 0, b.getWidth(),
    // b.getHeight(), m, true);
    // if (b != b2) {
    // b.recycle();
    // b = b2;
    // }
    // } catch (OutOfMemoryError ex) {
    // // We have no memory to rotate. Return the original bitmap.
    // }
    // }
    // return b;
    // }

    // public static <T> int indexOf(T[] array, T s) {
    // for (int i = 0; i < array.length; i++) {
    // if (array[i].equals(s)) {
    // return i;
    // }
    // }
    // return -1;
    // }

    // /**
    // * Make a bitmap from a given Uri.
    // *
    // * @param uri
    // */
    // public static Bitmap makeBitmap(int minSideLength, int maxNumOfPixels,
    // Uri uri, ContentResolver cr, boolean useNative) {
    // ParcelFileDescriptor input = null;
    // try {
    // input = cr.openFileDescriptor(uri, "r");
    // BitmapFactory.Options options = null;
    // if (useNative) {
    // options = createNativeAllocOptions();
    // }
    // return makeBitmap(minSideLength, maxNumOfPixels, uri, cr, input,
    // options);
    // } catch (IOException ex) {
    // return null;
    // } finally {
    // closeSilently(input);
    // }
    // }

    // public static synchronized OnClickListener getNullOnClickListener() {
    // if (sNullOnClickListener == null) {
    // sNullOnClickListener = new OnClickListener() {
    // public void onClick(View v) {
    // }
    // };
    // }
    // return sNullOnClickListener;
    // }
    //
    // public static void Assert(boolean cond) {
    // if (!cond) {
    // throw new AssertionError();
    // }
    // }
    //
    // public static boolean equals(String a, String b) {
    // // return true if both string are null or the content equals
    // return a == b || a.equals(b);
    // }

    // // Returns an intent which is used for "set as" menu items.
    // public static Intent createSetAsIntent(IImage image) {
    // Uri u = image.fullSizeImageUri();
    // Intent intent = new Intent(Intent.ACTION_ATTACH_DATA);
    // intent.setDataAndType(u, image.getMimeType());
    // intent.putExtra("mimeType", image.getMimeType());
    // return intent;
    // }

}
